1. Field of the Invention
The present invention relates to telecommunications and, more particularly, to methods for managing mobile node registrations and resource allocations.
2. Description of Related Art
Wireless telecommunications technologies are continuing to develop in order to provide enhanced multimedia (e.g., data) service to wireless customers. For example, a wireless telecommunications network may allow wireless customers to access the Internet, browse the World Wide Web, send and receive e-mails, and access other packet data services.
To access these packet data services, wireless customers may use mobile nodes, such as wireless telephones, wireless personal digital assistants (PDAs), and wirelessly-equipped laptop computers, that use various protocols to connect to the wireless telecommunications network. For example, a mobile node may use the Point-To-Point (PPP) protocol and either Simple IP or Mobile IP protocol to establish a data link with the wireless telecommunications network. Once a mobile node has established a data link with the wireless telecommunications network, it may use higher-level protocols, such as the Session Initial Protocol (SIP) and the Wireless Application Protocol (WAP) to access packet data services.
In establishing a data link with a mobile node, the wireless telecommunications network may allocate a network resource for that mobile node. For example, the wireless telecommunications network may dynamically assign an IP address for the mobile node, for either a Mobile IP or a Simple IP session. Because network resources, such as dynamic IP addresses, that the wireless telecommunications network has available to allocate to mobile nodes may be limited, it is often desirable to carefully manage these network resources. As a result, resources, such as dynamic IP addresses, are often allocated to mobile nodes for only limited time periods. If a mobile node maintains a sufficient level of activity during the time period, then the mobile node may be able to renew its resource allocation. Otherwise, the wireless telecommunications network may de-allocate the mobile node's network resources, so that the resources can be made available to other mobile nodes.
The activity that determines whether resources can be renewed is often measured as the amount of the mobile node's data traffic, i.e., the amount of data it transmits and receives. However, only some of the data traffic may relate to user activity, e.g., data traffic initiated by user activity. A mobile node may also generate data traffic automatically, as a result of applications provided in the mobile node. This automatic data traffic occurs regardless of whether the user is actively using the mobile node.
For example, when a mobile node successfully registers with a wireless telecommunications network using Mobile IP, the mobile node obtains a mobile node registration, which may include a dynamically assigned Mobile IP address. The mobile node registration is typically valid for only a registration time period. In an existing implementation, the mobile node attempts to renew the registration by attempting to re-register before the expiration of the registration time period, if there has been any data traffic during the registration time period.
If, however, the mobile node runs applications that generate automatic data traffic, there may always be data traffic during the registration time period, even if the user does nothing. Accordingly, the mobile node may continue to renew its mobile node registrations, and continue to use up an IP address, until the user logs off, switches off the mobile node, or moves out of range. This may lead to the inefficient result of the wireless telecommunications network maintaining an IP address for the mobile node even though the user is inactive.
Accordingly, there is a need to provide more efficient management of mobile node registrations and resource allocations.